There are 13 words that start with 'pesti'.
| pestier | pestiest | 
| pesticide | pestilent | 
| pesticides | pestilence | 
| pestiferous | pestilences | 
| pestilently | pestilential | 
| pestiferously | pestilentially | 
| pestiferousness | |
Note: These 13 words that start with 'pesti' are found from the USA & Canada version of the tournament Scrabble word list.